(1) Field of the Invention
The present invention relates to a device that facilitates mounting a panel closing off a window in a structure, and that facilitates removing such a panel. The present invention also relates to a vehicle provided with such a device, and to a method of implementing it.
More particularly, the invention lies in the restricted technical field of mounting/removing a panel closing off an opening in an aircraft structure.
(2) Description of Related Art
The term “panel” is therefore used below to mean a member that is advantageously transparent and that closes off a window in a structure. By way of example, this panel may comprise a pane of glass or indeed a window pane made of Plexiglas.
It is common to use adhesive for securing a transparent panel to a vehicle structure, and in particular to an aircraft structure. Thus, Plexiglas or glass windows are usually adhesively bonded.
For example a Plexiglas panel can be adhesively bonded directly to a structure of a fuselage in order to close off a bay. A bead of adhesive is then placed between the panel and the structure in order to perform the adhesive bonding.
In order to release a broken Plexiglas panel, an operator sometimes inserts a saw between said panel and the structure in order to cut through the bead of adhesive.
That technique is effective but lengthy and difficult to implement.
The beads of adhesive that are used in the field of aviation have a width that is large, being about two to three centimeters, and a thickness that is small, being about three millimeters. It is then difficult to position and to use a saw for releasing the panel without damaging the structure and/or the panel.
The releasing operation can then require the aircraft to be taken out of service for relatively long and costly time.
In addition, a glass panel sometimes comprises a pane of glass that is fastened to a support which is in turn adhesively bonded to a fuselage.
An operator can then remove the pane of glass from the support and then implement the above-described technique for releasing the support from the fuselage.
A technique for releasing a transparent panel is also known that is in common use for releasing windshields in the automobile field.
An operator drills a hole through a bead of adhesive.
The operator then threads a strong filamentary element usually referred to as a “piano wire” through the drilled hole. Two operators take hold of respective ones of the ends of the filamentary element so as to move said filamentary element between the panel to be released and the structure, thereby slicing through the bead of adhesive.
Once the panel has been disunited from the structure, an operator cleans the panel and the structure so as to remove the residue of the adhesive. By way of example, the operator might therefore heat the surfaces to be cleaned before applying a cleaning substance that is optionally of the antioxidant type.
That technique is advantageous. However, it is difficult or indeed impossible to implement on an aircraft having a wide, thin bead of adhesive that is particularly strong once in the set state. The force the operators need to apply to slice through such a bead of adhesive is too large for applying that technique.
In addition, the drilling step can be complicated to perform in view of the small thickness of the bead of adhesive.
Releasing a transparent aircraft panel is then a difficult operation.
The width of the bead of adhesive could be reduced in order to implement the method that is applied to an automobile windshield. However, the pressure and sealing conditions that apply to an aircraft panel appear incompatible with such a reduction in width.
The technological background includes Document U.S. Pat. No. 5,069,012 relating to using adhesive for bonding a panel to a structure.
That document proposes placing a bead of adhesive on the panel and arranging a seal between the panel and the structure. That seal is hollow and an extraction wire is placed inside it.
It appears difficult to apply that technique to an aircraft, since the beads of adhesive used in the aviation field are wide.
Similarly, Document U.S. Pat. No. 6,929,844 proposes placing an elastomer member on a contact surface of a panel. That member has a ridge provided with a groove open to the outside and receiving an extraction wire.
In addition, that member includes a plane portion integral with the ridge and with its contact surface, the groove in the ridge opening out onto a free face of said plane portion.
A bead of adhesive is then placed over the free face and over a pane of glass in order to fasten the pane of glass to a structure.
By pulling the extraction wire out of the groove, it is possible to slice through the bead of adhesive.
However, it appears difficult to slice through a wide bead of adhesive.
Document EP 0 367 662 presents a calibrated shaped-section member interposed between a bead of adhesive and a panel. An extraction wire is used for slicing through the calibrated shaped-section member.
Documents DE 37 22 657, FR 2 766 156, and DE 202 17 925 are also known.